1. Field of the Invention
The present invention relates to a communication system having in-vehicle terminals and a center (an information center) interconnected by radiocommunication. Moreover, the present invention relates to an in-vehicle terminal employed in the communication system.
2. Description of the Related Art
There is a communication system in which computer programs, to be installed in in-vehicle terminals, are distributed from a center by radiocommunication or the like. In the communication system, when a user wants to install a program such as a navigation system or video game in his/her in-vehicle terminal, or when a user wants to update an installed program, the user issues a request for downloading a program from his/her in-vehicle terminal to the center. The center downloads the requested program to the in-vehicle terminal by radiocommunication or the like.
At this time, the center wants to check if downloading the program to the in-vehicle terminal has been completed normally. Otherwise, the center wants to check if the downloaded program is operating normally while being compatible with the software and hardware environment of the in-vehicle terminal. Through this checking, the center confirms that the program has been distributed to the user. At the same time, the in-vehicle terminal can be kept safe. Moreover, after checking, the center can charge the user for the service.
In contrast, in conventional communication systems, a center does not have a means for performing the checking. After a program is delivered to an in-vehicle terminal, the program is at the user""s disposal. The center cannot therefore sell a program even after confirming that the program satisfies the user. Moreover, even if an abnormality occurs during downloading or after activation of a program, the center cannot cope with it swiftly.
This application claims priority from Japanese Application No. 11-9649, filed Jan. 18, 1999, the contents of which are incorporated hereinto by this reference.
An object of the present invention is to provide a communication system for downloading programs from a center to in-vehicle terminals. Herein, the center can check if downloading has been completed normally or if a downloaded program is operating normally in an in-vehicle terminal.
The present invention has been devised in order to accomplish the above object. According to the present invention, there is provided a communication system having in-vehicle terminals and a center interconnected by radiocommunication or the like. Herein, after a program is downloaded from the center to an in-vehicle terminal, the in-vehicle terminal transmits information, which indicates that the program has been activated, to the center according to the timing of activating the downloaded program. The timing of activating the program includes the timing that the program is activated first and the timing that the program has been activated a certain number of times or more.
Consequently, the center becomes aware that the program has been downloaded without any problem and that the program has been activated normally. The center can thus confirm that the user""s in-vehicle terminal is safe. Moreover, the center can use the results of checking as a criterion for charging the user.
According to the present invention, there is provided an in-vehicle terminal in which, if the state of communication becomes improper during downloading of a program, downloading is suspended, or downloading is automatically restarted. When downloading is suspended, if necessary, the in-vehicle terminal requests downloading of the program again. For automatically restarting downloading, when the state of communication becomes improper, the state of downloading attained when communication is cleared is recorded. When the state of communication is recovered, the state of downloading is reported to the center. According to the state of downloading reported from the in-vehicle terminal, the center restarts downloading of the program from the middle of the program, or more particularly, downloading of a portion of the program that has not been transmitted.
According to the present invention, the in-vehicle terminal has either of a facility for suspending downloading when the state of communication becomes improper and a facility for automatically restarting downloading. Alternatively, both the facility for suspending downloading and the facility for automatically restarting downloading may be made available so that a user can select either of them.
Furthermore, according to the present invention, the in-vehicle terminal can cope with an event such as an ACC power supply being turned off during downloading. As far as an in-vehicle terminal is concerned, when an ignition key is removed during downloading, an ACC power supply may be turned off. According to the present invention, the power supply of the system is changed from the ACC power supply to a +B power supply that is a backup power supply in order to continue downloading. Otherwise, downloading may be suspended or automatically restarted. Even in this case, a user can select the suspending facility or the automatically restarting facility.
According to the present invention, when a program is downloaded from a center to an in-vehicle terminal or when a downloaded program is operated in an in-vehicle terminal, if any trouble occurs, a countermeasure can be taken quickly. Consequently, the users"" jobs are hardly interrupted and the users"" satisfaction can be upgraded. Moreover, when it is necessary to charge users for services, it can be judged correctly whether users should be charged.